Matildas' coach Tom Sermanni says his team have the weapons to trouble Brazil and can't be intimidated in their opening women's World Cup match in Germany.

Australia open their campaign in Moenchengladbach on Wednesday (early Thursday AEST) against a No.3 ranked Brazil side desperate to shed the bridesmaid's tag after finishing runner-up at the last World Cup and the last two Olympics.

Sermanni believes his 11th-ranked team is deeper and more mobile than the one he guided to the World Cup quarter-finals four years ago.

Experienced stalwarts like midfielders Heather Garriock and Collette McCallum and mercurial striker Lisa De Vanna have been joined by a new generation of emerging youngsters.

But the Matildas' defence, marshalled by captain and veteran goalkeeper Melissa Barbieri, will be severely tested by prolific Brazil strikers Marta and Cristiane.

Five-time World Player of the Year Marta has scored an astonishing 76 goals in 69 internationals. Cristiane, who netted the winner in their 3-2 quarter-final win over Australia at the last World Cup, has scored 41 goals in 56 internationals.

"I think the first really critical thing is to harness their strikers, because that's where they've got some real potency," Sermanni said.

"The second thing is to play the type of football that we've been trying to play and working on for the last couple of years and have the confidence to play that type of football.

"If we do that we feel we have got the weapons in our team that can cause them some defensive problems.

"I think it's really key that we look at the good things that we can do and the positive results that we've had and not go in there worrying about the aura of Brazil."

Given Australia's squad contains seven teenagers, there must be some risk that Matildas players will be in awe of their powerhouse rivals.

However, Sermanni said because so many of his players were new to international football, they hadn't developed any fear of the opposition.

"There's a kind of youthful innocence about this squad in a sense, that they don't seem to be that frightened of whoever they come up against, because often they don't actually know the players that well or know their reputations that well," Sermanni said.

He rated defending champion Germany favourites followed by Brazil and the United States.

"I honestly think from number three or four to 12 in the world that the gap is just unbelievably close," Sermanni said.

"Any of those teams from the three Asian teams through to the top Europeans and Canada, if they get on a roll, could go far into this tournament."